Portable flashlights are used for the prevention of disasters and the maintenance of public security at night, and are thus made waterproof so as to enable them to be used in rainy weather. As disclosed in Japanese Utility Model Publication No. 58-24353, a push button switch fitted thereover with a rubber cap is applied to the prior art portable type flashlights. This system assures a sufficient waterproofing effect for a switch portion. However, while this type of switch structure may be applied to portable flashlights of the type that have a large inner space, it cannot be applied to portable flashlights of the slide type switch, which have a wide range of mobility and are easy to handle, because the push button projects from the body, and a large inner switchover mechanism is provided. For that reason, it is desired that the prior art slide type switch should be of the waterproof structure.
However, the reason why the prior art slide type switch cannot be made waterproof is that, as shown in FIG. 4, integral connection is made between a slide button 2 and a switchover hook 3, both mounted on the upper face of a switch portion of a body 1, via a rod 4, so that, when to-and-fro movement of the slide button 2 takes place, the switchover hook 3 moves to-and-fro together with the rod 4 in operable association with the push button 2. In other words, it is required to provide a slit 5 for to-and-fro movement of the rod 4 in a portion of the switch mount of the body 1. However, it is not possible to make that slit waterproof.